A Plasmodium falciparum protein kinase with two unusually large kinase inserts.

A protein kinase gene (PfPK1) has been isolated from the human parasite Plasmodium falciparum by using a mixed oligonucleotide pool which corresponds to a highly conserved region of serine/threonine protein kinases. The gene, which contains one intron, encodes a protein with a predicted length of 909 amino acids. The predicted protein contains all the conserved sequences characteristic of a protein kinase catalytic domain.

Two major phosphoproteins of Plasmodium falciparum are heat shock proteins.

Two major phosphoproteins of Plasmodium falciparum could be identified by partial amino acid sequencing as the plasmodial members of the hsp 70 heat shock protein family, Pfhsp and Pfgrp. According to phosphoamino acid analyses of Pfhsp and Pfgrp isolated from [32P]orthophosphate-labeled malarial cultures, both proteins were phosphorylated in Ser and Thr. While Pfhsp contains higher amounts of labeled phosphoserine, Pfgrp contains higher amounts of phosphothreonine.

An 88-kDa protein of Plasmodium falciparum is related to the band-3-binding domain of human erythrocyte ankyrin.

Three tryptic-peptide sequences of an 88-kDa pair of phosphoproteins of the malaria parasite Plasmodium falciparum were determined. They exhibit a striking similarity to corresponding sequences of the 89-kDa domain of human erythrocyte ankyrin. [35S]Methionine labeling of the two proteins demonstrated their parasitic origin.

Localization and stage specific phosphorylation of Plasmodium falciparum phosphoproteins during the intraerythrocytic cycle.

Fifty-nine Plasmodium falciparum specific phosphoproteins with molecular weights between 15,000 and 192,000 were analyzed by SDS-PAGE and two-dimensional gel electrophoresis. 40 phosphoproteins were identified by [gamma-32P]ATP labeling of cell lysates, 19 by [32P]orthophosphate labeling of parasitic cultures in vivo. Changes in the phosphorylation pattern during the infectious erythrocytic cycle were determined for all proteins.